Railway-traffic-controlling apparatus



1930. H. G. BLOSSER ET AL 1,784,815

RAILWAY TRAFFIC CONTROLLING APPARATUS Filed Sept. 20, 1929 A Af h Z0 .1 Mg? :21 F

2 Ba B R1 WC 2: 8 4 F 4: m 4 f 5/ \5 1 W WM awaw Patented Dec. 16, 1930 UNETD STATES PATENT OFFICE HERMAN G. BLG SSER, OF PITTSBURGH, AND RONALD A. IVECCANN, 0F SWISSVALE, PENNSYLVANIA, ASSIGNOB-S 'IQ THE UNIGN SWITCH 8r. SIGNAL COMPANY, OF SWISSVALE, PENNSYLVANIA, A CQRPOBATION OF PENNSYLVANIA RAILWAY-TRAFFIC-CONTROLLING APPARATUS Application filed September 20, 1929. Serial No. 394,054.

Our invention relates to railway traffic controlling apparatus, and particularly to the train-carried portion of automatic train control systems of the coded continuous inductive type.

One feature of our invention is the provision of means for preventing improper operation of the train-carried apparatus in response to shock excitation while the train is traveling in territory not equipped for automatic train control.

We will describe one form of apparatus embodying our invention, and will then point out the novel features thereof in claims.

The accompanying drawing is a diagrammatic view showing one form of apparatus embodying our invention. 7

Referring to the drawing, the apparatus, all of which is carried on a train, comprises a master relay 1) having an armature 18 which is adapted to oscillate in response to impulses received from the trackway. This armature coacts with fix-ed contacts 18 and 18 in such manner that the contacts are closed alternately while the armature is in operation. During the operation of the armature, direct current is alternately supplied to the two halves of the primary 19 of a transformer T, from a source the terminals of which are designated B and C; that is to say, when contact 1818 is closed direct current flows in one direction through the lower half of primary 19, whereas when the contact 1818 is closed direct current flows in the other direction through the upper half of pri mary 19. It follows that when the armature 18 is in operation, alternating current will be delivered from the secondary 20 of transformer T. The lower portion of the secondary 20 is connected with the input terminals of a full-wave rectifier 7& through a circuit which will be traced hereinafter, and the output terminals of this rectifier'are connected with a relay R which is used for train control purposes. It follows that when the armature 18 of the master relay D is in opera tion, and when the input circuit for the rectifier h is closed, unidirectional current will be supplied to relay R so that this relay will be energized.

The parts of the apparatus thus far described, are the same as the parts having corresponding reference characters in an application filed by L. V. Lewis on August 2, 1927, Serial No. 210,165, for railway trafiic controlling apparatus. The aforesaid application fully describes and explains how the master relay D is controlled from the trackway, and how this relay in turn causes alternating current to be delivered by the secondary 20 of transformer T, so that further explanation of these features is not required for the present disclosure. Ordinarily other relays will be supplied with current by the secondary 20 of transformer T, but these other relays form no part of our present invention and'are omitted from the disclosure for the purpose of simplicity.

Assuming that the circuit including the secondary 20 and the rectifier h is always closed, as it is in the aforesaid Lewis application, and assuming that the master relay D is momentarily energized by shock excitation while the train is passingthrough territory not equipped for automatic train control, it is possible for relay R to become momentarily falsely energized, but this is undesirable because the apparatus which is usually associated with relay R will then necessitate acknowledgment on the part of the engineer in order to permit the train to proceed, or in order to prevent a false stop indication by the cab signal. In order to prevent false energization of relay R by shock excitation we have provided means requiring oscillation of the master relay armature 18 for a given interval of time before relay R will close.

This means comprises two thermal relays A and A and two auxiliary slow-releasing relays B and B. Each thermal relay A comprises a heating winding 7, and a normally open contact 3 which becomes closed after the Winding 7 has been energized for a given interval of time. The circuit for the heating winding 7 of relay A is from terminal B, through contact 18-18" of relay D, the heating winding 7, and a back contact 6 of the associated auxiliary relay B to terminal C of the same source of current. Auxiliary relay B is provided with a pick-up circult which passes from terminal B, through contact lS-1S, contact 3 of thermal relay A and the winding of relay B to terminal C. This relay B is also provided with a stick circuit which passes from terminal B, through contact 1818, front contact 4 of relay B and the winding of relay B to terminal C. The circuits for relays A and B are the same as the circuits just traced for relays A and 13 except that they include the other contact 1818 of the master relay D.

The input circuit for the rectifier k passes from an intermediate point of secondary 20 of transformer T, through wire 10, front contact 5 of relay B front contact 5 of relay B, wire 8, rectifier and wire 9 to the lower terminal of secondary 20. It follows that both relays B and B must be closed in order to energize the rectifier 7L and the 1c lay R As shown in the drawing, the master relay D is at rest with contact 18l8 closed, so that auxiliary relay B energized and auxiliary relay B is (lo-energized. Assuming now that armature 18 of relay D commences to oscillate, the closing ofcontact 18-18 will close the circuit for the heating winding 7 of relay A and after this contact has been closed seve al times, contact 3 of relay A will close, thereby closing the pick-up circuit for relay 13 which will accordingly become energized. This will open at back contact 6 the circuit for the heating winding 7 of relay A so that relay A will become deenergized, but relay B will remain energized 2y virtue of its stick circuit. The slow-acting characteristic of this relay prevents it from releasing between periodic closures of contact 18-18 while relay D is in operation. Relay B will remain energized because of the periodic closing of contact 18l8. It follows that after relay D has been in operation for a short interval. of time, the input circuit for rectifier 7:1 will become closed at both contacts 5 of the auxiliary relays B and 13 so that relay R will likewise become energized.

\Vhile the train is passing through territory not equipped for automatic train control, the armature 18 of relay D may be falsely operated due to shock excitation, this being particularly true in the case of railroads of the electric propulsion type. Inasmuch as one or two operations of the armature 18 will not result in the energization of whichever relay B or B is open, it follows that shock excitation will not result in false energization of the train control relay R Obviously it the relay D comes to rest with contact l8-18 closed when the train enters non-equipped territory, relay B will remain energized and relay B will become de-energized, but the operation will then be the same as before, except that when the oscillation of relay D again begins, it will be necessary for relay B to become energized before relay R will be affected.

Although we have herein shown and described only one form of apparatus embodying our invention, it is understood that various changes and modifications may be made therein within the scope of the appended claims without departing from the spirit and scope of our invention.

Having thus described our invention, what we claim is:

1. Railway train carried governing apparatus comprising a master relay controlled from the trackway and having an armature adapted to oscillate in response to impulses received from the traekway, two thermal rclays each having a heating winding and a normally open contact which closes after the winding has been energized for a given interval of time, two auxiliary slow-releasing relays associated with said two thermal relays respectively, a circuit for the winding of one thermal. relay including a contact closed when said master relay armature is in one extreme position and a back contact of the associated auxiliary relay, a circuit for the winding of the other thermal relay including a contact closed when the armature of said master relay is in the other extreme position and a back contact of the associated auxiliary relay, a pick-up circuit for the first auxiliary relay including said first master relay armature contact and the contact of the associated thermal relay, a stick circuit for said first auxiliary relay including its own front contact and said first master relay armature contact, a pick-up circuit for the second auxiliary relay including said second master relay armature contact and the contact of the associated thermal relay, astick circuit for said second auxiliary relay including its own front contact and said second master relay armature contact, a train control relay, and means for energizing said train control relay while said master relay armature is oscillating if and only if the front contacts of both of said auxiliary relays are closed.

2. Railway train carried governing apparatus comprising a master relay controlled from the trackway and having an armature adapted to oscillate in response to impulses received from the trackway, two thermal relays each having a heating winding and a normally open contact which closes after the winding has been energized for a given interval of time, two auxiliary slow-releasing relays associated with said two thermal relays respectively, a circuit for the winding of one thermal relay including a contact closed when said master relay armature is in one extreme position and a back contact of the associated auxiliary relay, a circuit for the winding of the other thermal relay including a contact closed when the armature of said master relay is in the other extreme position and a back contact of the associated auxiliary relay, a pick-up circuit for the first auxiliary relay including said first master relay armature contact and the contact of the associated thermal relay, a stick circuit for said first auxiliary relay including its oWn front contact and said first master relay armature contact, a pick-up circuit for the second auxiliary relay including said second master relay armature contact and the contact of the associated thermal relay, a stick circuit for said second auxiliary relay including its own front contact and said second master relay armature contact, a transformer, means for energizing the primary of said transformer While the armature of said master relay is oscillating, a train control relay, and a circuit for said train control relay including the secondary of said transformer and a front contact of each of said auxiliary relays in series.

In testimony whereof We affix our signatures.

HERMAN G. BLOSSER. RONALD A. MOCANN. 

